1. Field of the Invention
The present invention relates to friction clutches, especially for motor vehicles, that include one or more friction discs and pressure plates.
The present invention is more particularly concerned with clutch mechanisms which are incorporated in a unit consisting of such a clutch.
2. Description of the Related Art
As is known, a clutch mechanism, such as is described in the document U.S. Pat. No. 3,499,512, comprises a hollow cover plate for fastening the clutch mechanism on a reaction plate, a diaphragm with an outer periphery in the form of a Belleville ring, mounted pivotally on the cover plate by means of posts, a pressure plate acted on by the diaphragm and having a projecting seat for abutment of the outer periphery of the Belleville ring of the diaphragm, and tangentially oriented resilient tongues coupling the pressure plate to the cover plate in rotation but with axial mobility, wherein the posts are fixed to the base of the cover plate and have heads which are profiled so as to constitute a secondary abutment for the inner periphery of the Belleville ring of the diaphragm, in facing relationship with a primary abutment carried by the base of the cover plate.
The above mentioned posts enable overall axial size of the clutch mechanism to be reduced, and are fixed to the base of the cover plate.
Conventionally, the tangential tongues are secured by riveting to respective radially projecting lugs carried by the pressure plate at its outer periphery, and to a radial flange carried by the cover plate at its outer periphery.
This results in an increase in the radial dimension of the pressure plate, because of its lugs.
An object of the invention is to reduce the radial size of the pressure plate, while enjoying the benefit of an arrangement having posts with profiled heads.